Threading die



`Buma 27, 1939'. w. J. HoGG THREADING DIE Filed May 3, 1958 8 Sheets-Sheet l O a) D D INVENTOR.

Imi @mw uffi/'Ugg ATTORNEY.

W. J. HOGG THREADING DIE June 27, 1939.

Filed May 3, 1958 8 Sheets-Sheet 2 INVENTOR W. J. HOGG THREADING DIE June. 27, 1939.

8 Sheets-Sheet 3 Filed May 5, 1958 I INVENTOR 77125666071,

A TTORNE Y J. HQGG 293635 THREADNG DIE Filed May s, 1938 8 sheets-sheet 5 ATTORNEY lume 27, w39., w.yJ. HOGG 2,163,598

THREADING DIE Filed May 3, 1938 8 Sheets-Sheet 6 INVENTOR a m JHUQQQ A TTOVE Y Jun@ 27? 21939. W L H06@ 2,163,59

THREADING DIE Filed May 3, 1938 8 Sheets-Sheet 7 lfm/175. MM Z Q IN VEN TGR mm .Iggg

jm@ 27, ma, w HQGG 291535 THREADING DIE Filed May 3j 1938 8 Sheets-Sheet 8 Y l, mVENmR ATTORNEY Patented June 27, 1939 UNITED STATES THREADING mn lWilliam J. Hogg, Cleveland, Ohio, assignor to The National Acme Company, Cleveland, Ohio, a

corporation of 0h10 Application May 3, 193s', yserial No. 205,718

31 Claims.-

This invention relates to threading tools 'and more particularly topipe dies adapted for threading pipes suchas oil well pipes usually of large diameter, the object of the invention being to provide an improved pipe die having automatically shiftable chasers or cutters for cutting a tapered pipe thread and which die is simple in construction and eilicient in operation.

A further object of the invention is the provision of an improved die of the type specied in whicln the chasers or cutters are positively and, therefore, more efliciently controlled especially during their expanding movement, thereby ensuring that each chaser will do an equal amount of cutting and be prevented from pulling away from the controlling sleeve and take a heavier cut whereby a better tapered and smoother thread is obtained, and in which the die has a large range so that a number of different tapers can be readily obtained as well as a ne adjustment of taper by the mere manipulation of very simple adjusting means.

A` further object of the invention is the-provision of interchangeable chaser'carrying members to permit the expansion of the die beyond the limits of its adjustingmeans to enable the die to cut an increased number of pipe sizes.

A further object of the invention is the provision of means for obtaining a fine adjustment of taper which is very advantageous in cutting Work accurately since a great variation results in the threading of different materials and also in the feed of various machines.

A further object of the invention is the provision of means for permitting adjustment for length of thread without aiecting the diameter of the threaded pipe at the point of opening of the die head.

A further object of the invention is the pro'- vision of means for adjusting the diameterof thread cut by the die without affecting the length or taper of thread cut.

A still further object of the invention is the provision of means for closing the die either from the inside oroutside of the die head and also by means of a hand lever if desired.

In the drawings accompanying and forming a part of this specication, Fig. 1 is a side elevation of this improved die head.

Fig.` 2 is a transverse section on the line 2-2 of Fig'. 1.

Fig. 3 is a rear end view of the die.

Fig. 4 is a front end view of the die.

Fig. 5 is a detail of the chaser block and guide Way.

Fig. 6 is a longitudinal section taken on'line 6--6 of Fig. 4.

Fig. 7 is a transverse section taken on line 1-1 of Fig. 6.

Fig. 8 is a plan view of the inner slide` partly in section.

Fig. 9 is a perspective view of the trigger locking and releasing member.

Fig. 10 is a view of the resetting block and' the guide therefor.

Fig. 11 is a perspective View of the resetting block.

Fig. 12 is a partial transverse section of the mechanism controlling the upper part of lthe control lever and adjacent mechanism.

Fig'. 13 is a horizontal section on line I3-l3 of Fig. 12.

Fig. 14 is a detail in section of the guide openfing for the yoke controlling pin.

Fig. l5 is an enlarged front view of the control lever housing showing in detail the adjusting means for various tapers.

Fig. 16 is a perspective view of the adjustable control block for the taper control lever.

Fig. 17 is a partial sectional view on line ll-I 1 v of Fig. 3, illustrating the trip mechanism and also the emergencyftripping means, and

Fig. 18 is a perspective view of the trip plate for tripping the` die.

Similar characters of reference indicate corresponding parts in the several views.

Before explaining in detail the present improvenient and mode of operation thereof, I desire to have it understood that the invention "is not limited to the details of construction and arrangement of parts which are illustrated in the accompanying drawings since the invention is lcapable of other embodiments, and that the phraseology which I employ is for the purpose of description and not of limitation.

In the operation of this die, it is practicable to rotate either the die or the Work and it is, likewise, practicable to feed either the die or the work but, in the present instance, I am describing the die rotating relative to non-rotatable worl; with the work advancing accordance with the usual lead screw of the machine while the die is held against axial movement.

'I'his improved die head, in the preferred form thereof, comprises a body 2 having a flanged shank 3 and pilot 4 adapted to t into the spindle of the machine and this ange 3 is provided with a series of holes for facilitating the bolting of the die rmly to the spindles.

To the front -end of the die body there is atthe front face of this nose piece 6 is provided with removable hardened plates 1 to provide for inexpensive replacement when necessary.

'I'he nose piece 6 is provided with a series of radial slots to receive die block slides 9 to which are secured the chaser holding blocks I6 carrying, in the present instance, a series of circular chasers II, and the die block slides 9 are shifted inwardly and outwardly by a series of tongued cam rods I2 passing through openings I3 in the nose piece and slidingly cooperating with any of a series of tapered cam slots I4 of the die block slides 9. This sluiting movement of the die block slides 9 thus causes an inward and outward movement of the chaser blocks I and the chasers II. These cam slots I4 will be referred to hereinafter in connection withl the diameter adjusting means and the cam rods I2 will also be hereinafter referred to in connection with the taper control.

Within the diebody is an inner slide member designated generally,by I5, to the front end or extension I1 of which is attached an adjustable plate or ring I6 which will be designated herein as a trip plate in contradistinction to the tripping means hereinafter described. This extension I1 is secured to the front of the slide I5 by suitable screws I8.

Secured to the inner slide I5 and forming a part of the trip assembly is a member or block I9 held thereto by suitable screws 20 and dowels 2| and 22 (s'ee Fig. 3). This member I9 carries 'two pins 23 and 24, one of which, 23, is used when threading 1%" and 1% taper per-foot of threadV and the other, 24, of which is used when threading fig" taper per foot.

The illustrationsshow a die having a trip plate I6 set for threading a 5%" 0. D.fpipe'with a short thread approximately 2% long. On short threads of this type, the`Y trip plate is moved backward under rapid traverse of the carriage until the pipe comes close to the chasers. The lead nut of the machine is then thrown in and the pipe is fed in the proper amountrelative to the pitch of the thread being cut.

Taper control The taper control for the die comprises a compound pivotal movement,` one movement being obtained by a lever 25 pivoted at its `outer end n an adjustable pin 26 so positioned as to remain at all times during the threading action in the same position relative to the axis of the die. The slot 26 permits the lever to move in an arc about this pin 26. The other end of this lever has a slot 21 adapted to slide on the pin 23.

As the trip plate I6, together with the inner slide and the member I9 carrying the pin 23, is moved back by the travel ofthe work during the threading action, the inner end of the lever 25 carried by the pin A23, which moves back parallel to the axis of the die, is caused to move back,the slot 21 permitting the inner end of the lever to swing in an arc.

Carried by this lever 25 is a stud-28 adapted to slide in a line parallel to theaxis of the die in slots 29 of a block 53 carried by the body. "I'hus, the three pivotal points 23, 26 and 28 are at all times at the same distance from the axis of the die and any movement of any of these points dur- A ing the threading action is parallel to the axis of the die and the stud 28 is caused to move back in the ratio of the. difference (the center disaieasoa tance) of 23 is to 26 as (the center distance) 26 is to 26 which, in the illustration shown is a ratio `of 4 to 1.

Th other movement is obtained by a two-piece yoke 29 secured together by a ring 36 around the outside of the die and secured to the anged face '36 of the yoke and carried by ribs 30 of the yoke (see Fig. 1). This yoke is adapted to be carried pivotally by a stud 3I extending through the yoke 29 and size adjusting blocks 32 hereinafter described.

At the opposite side of this yoke 29 is the stud 28 of the lever 25 so that, as the lever 25 is moved back and with it the stud 26, this opposite side of the yoke 29, likewise, will be moved back, thereby pivoting on the stud 3I.

Midway betweenthe studs 28and 3| on each side of the yoke is ylocated a pilot screw 33 and within the yoke 29 and exteriorly of the body 2 is a sliding sleeve 34 having a flanged headi/or ring 35, the pilots 36 of the pilot screws 33 being secured to this sleeve 34. Therefore, as the pin or stud 26 moves back with the pivotal action of the yoke 29 on the stud 3l, these pilots 36 will be moved back one-half the distance of the stud 28 and with them the sleeve 34 will be moved back the same distance.

The cam rods I2 hereinbefore mentioned are secured to the head 35 of the sleeve 34 by any suitable means. These cam rods have a laterally extending inclined tongue to engage any of the cam slots I4 of the block slides 9. The angle of this tongue and that of the slots is eight times the angle of a 1% per I foot tapered thread. Therefore, as the ratio of movement of the pin 23 to the stud 28 is four to one and the ratio of movement of the stud 28 relative to the pilots 36 is two to one, 'the movement of the sleeve 34 and cam rods I2 is one to eight relative to the inner slide I5. Thus, since the angle on the cam rods is eight times the angle of 3/4" to one foot taper, the die blockI 9, together with the chaser blocks I8 and chasers II will be'expanded 5X1" per one foot as the pipe is fed into the die.

The pivot pin 26 is adjustable and can be moved outward suiliciently to thread H" taper per foot and inward sufficiently to thread I1%," taper per foot and, if necessary, to cut 2%4" taper per foot.

When it is desired to cut a taper per foot, it is merely necessary to substitute a longer lever 25' (see dotted lines, Fig. 6) for the lever 25 and use the stud 24 instead of the stud 23 and this gives a greater ratio between 24 and 26 relative to 26. In s3 doing, it is necessary to remove the stud 23 soLas not to interfere with the long lever 26'.

Tripping mechanism T'he tripping mechanism comprises a trigger 31 (see Figs. 7, 9, 10 and 17) shown as a curved member for the purpose of obtaining sumcient' side bearing, fitted into a slot machined in the body 2 and pivoted to the body 2 by a pin 38 (see Fig. 7). v

A spring 39 is located between one end of the trigger and the bottom of the slot in the die body 2 whereby thisA end of the trigger is held in engagement with a slot 46 in the adjusting and tripping block 4I `whereby the trigger holds the block 4I from being forced back by the tension of the springs 42.

The chasers are opened at the end of the out as follows:

'I'he work in contact with the trip plate I6 moves the trip extension I1 together with the in- 75 ner slide I5 back in the die body whereupon a`flat trip piece 43, secured to the inner slide by screws 44 (see Fig. 17) having at one end thereof a cam 45, is brought into contact with the end of the trigger 31 as at 46 at a predetermined time according to the length of the thread to be cut on the work. This contact of the cam 45 with the trigger 31 swings the trigger on its pivot whereby the opposite end of the trigger swings inwardly and out of the slot in the block 4I, thus permitting the block 4| to move to the rear of the die under tension of the springs 42, thereby to expand the chasers.

Emergency tripping mechanismV The die may also be tripped at any time by an emergency trip located in the shank of the die. For this purpose, a pin 65 (see Figs. 3, 10 and 17) having a beveled end 66 is located in the die shank and is kept from turning by means of the pin 61 (see Fig. 3).

The beveled end of this pin 65 contacts the beveled end 68 of a spring pressed pin 69, the other end of which has a beveled end 10 in contact with a beveled slot 1I in the side of the trigger 31. Pressure on the pin 65 causes it to move inwardly, thus forcing the pin 69 to move the trigger 31 outwardly, thus releasing the block 4I and so tripping the die.

Diameter adjusting mechanism In the block 4| is fastened an adjustable block 32 that carries the pivot stud 3| of the taper coiitrol yoke 29. Since the die is designed to trip when the automatic tripping means is at the same point each time, it will thus cut the same diameter of thread at the large end of the pipe even though the adjustment is changed for length of thread as hereinafter described.

As hereinbefore described, the stud 3| forms the pivot point of the taper control yoke and does not move while the die is cutting the thread but when adjustment for diameter is required, this stud 3| is adjusted as follows:

For an increased diameter of thread, the screw 48 which may be graduated for fine adjustment if desired, is loosened and the screw 49 is tightened. This action causes the angular clamp 50 to be forced inwardly and the angular clamp 50' outwardly which, in turn, moves the adjusting block 32 rearwardly. When the desired rearward movement of this block has been obtained, the screws 48and 49 are tightened, thereby7 locking the block 32 securely in place.

Since the stud 3| extends through the taper control yoke 29, movementof this adjusting block 32 rearwardly moves the stud 3| back together with the yoke 29, the pilot 36, sleeve 34 and cam rods I2 and as these cam rods I2 move back, the die blocks 9 together with the chaser blocks II) and chasers II, are moved outwardly and an increased thread diameter is obtained. If the screw 49 is loosened and the screw 48 tightened, a reverse movement of the adjusting block 32` is obtained, resulting in a thread of smaller diameter.

The aforementioned procedure is for fine adjustment from .0005 to 116" large or small.

Another adjustment for size is obtained by using the various slots I4 in the die block 9. In the particular illustration set forth, there are four of these slots I4, although any desired number may be used. If the tongues on the cam rods I2 are inserted in the slots of block 9 nearest the center, av large diameter will be threaded with the same chaser blocks II) and chasers II. As each slot toward the outside of the blocks is used, a smaller diameter can be threaded. By the use of the i'lne micrometer adjustments of the screws 4S and 49 and the slots I4 in the die blocks 9 it will be noted that a large range loi? sizes can be threaded with a single set of blocks and chasers.

`A change of :size can also be obtained by the use of several sets of die blocks 9 or chaser blocks I0. By using. various diameters of chasers II or by using holders for rectangular blades, further changes in size can be obtained.

Adjustment for taper The adjustment for taper is controlled by moving the square-headed pin 26 toward the axis of the die for low taper adjustment and away from the axis of the die for high taper adjustment.

In the illustrations (see Figs. 6, 13 and 15) the short lever connected with the upper pin 23 and pin 26 is for cutting a thread approximately 3A, taper per foot. When a greater taper is desired, it is merely necessary to loosen the screws 5Iv sufficiently to permit this block 5| to be moved out on the adjusting block 53 to the desired point, the mating serrations 52 in the blocks 5I and 53 serving to ,hold the blocks sel curely together when the screws 5| are tightened.

The two elongated slots 5|" in the adjusting block 5I (see Fig. 16) permit this block to be moved inwardly and outwardly to give a fine adjustment of taper. The taper can be adjusted plus or minus le to a foot.

If a taper per foot is desired, the pin 26 can be moved to another hole 54 in the block 5I and the block moved so that this pin 26 will be closer to the axis of the die and a fine taper can be adjusted at this point to obtain le" taper per foot plus or minus as hereinbefore explained by the adjustment of the block 5|. By leaving the pin 26 at this same point but substituting the f longer lever 25 shown in dotted lines in Fig. 6 for the short lever 25 and using the pin 24 instead of the pin 23, a g" taper per foot will be obtained and a plus or minus adjustment can be had by moving the block 5I inwardly or outwardly. When using the long lever 25' the pin 23 used with the short lever will have to be removed as hereinbefore explained to prevent its interfering with the movement of the long lever.

While the foregoing provides for three tapers, it is obvious that many others may be obtained by the use of various spacings at the control points.

Adjustment for length of thread When the longest thread that the die will make is desired, the inner slide is brought forward as far as possible and the trip plate I 6 adjusted rearwardly by removing the screw 55 which allows the key 56 to be removed. This key 56 ts in a keyway in the threaded part I1 and in one or more slots in the trip plate holder 51. When the key is removed, the trip plate holder 5I together with the trip plate I6 can be adjusted rearwardly. If so adjusted until the front face of the trip plate I6 comes in line with the front face ofthe chasers, the full expanding action takes place.

When the pipe or work is moved into the die, a longer thread can be cut if the trip plate is further vadjusted rearwardly whereby the chasers y will cut -the length of the chaser before commencing to expand.

The key 56 keeps the threaded part 51 from turning when the end of the pipe contacts the trip plate I6 if either the pipe or die is revolving and the parts 51, I6 and 58 are so constructed that when the pipe is against the face of the trip plate I6, it can rotate with the pipe by hav- 5 ing the nuts 59 tightenedon the end of the part 51 rather Ythan on the face of theftrip plate I5. Larger or smaller rings I6 can be made to suit the pipe being threaded since this ring must be larger than the hole in the ypipe or work and 10 smaller than the root diameter of the thread at the small end of ther pipe or work in order for the chasers to clear it.

If a short thread is desired the trip assembly 51, I6 and 58 is moved out away from the die chasers. Y

If the die is used to cut a full length of thread, say 6 inches before tripping and is set, as above described, for threading such full length of thread, and a 5" length of thread is required, this trip plate I6 is moved forwardly from the above setting one inch. Thus, the end of the lpipe or work when it contacts the plate I6 will move one inch toward the chaser before contacting the chaser. Therefore, the die will use one inch expanding action before starting to thread and the die will trip after five inches of thread have been cut.

Resetting the die Resetting the die in one way is obtained by a lever or fork that can be inserted in the ring -29 at a point near the block 4l. By means of this fork or lever, the yoke or rlng'f29 can be moved toward the front of the die and with it the block 4I until the slot 40 in this block 4I is in position to permit the trigger 31 to move thereinto by the pressure of the spring 39. This forms an outside resetting means.

The die can also be reset by having a yoke or pad brought up against the ring 30 until the 40 block 4I is moved into position to permit the trigger 31 to move into the slot.

The two springs I2 move the inner slide forwardly in the die as soon as the pipe or work is removed from the die. l

This die is also constructed so that it can be reset by inside means. As the pipe is removed from the die when the threading action is completed, the springs 42 move the inner slide forward until a lug 60 fastened to the inner slide by 50 the screw 6I and pin 62, comes in contact with a lug 63 fastened to the block 4I by screws 64. At this time a rod or any suitable means can be inserted through the back of the die to move the inner slide further forward, whereupon the lug 5 E0 will move the lug B3 forwardly with the block 4I until the slot in the block 4I has been moved into position.A to permit the trigger 31 to enter, and maintain the block in position until tripped as hereinbefore described.

It is to be understood that, by describing in detail herein any particular form, structure or arrangement, it is not intended to limit the invention beyond the terms of the several claims or the requirements of the prior art.

Having thus -explained the nature of my invention and described a way of constructing and using the same, although without attempting to set forth all of the forms in which it may be made or all of the modes of its use, I claim:

1. A die comprising a body, an axially shiftable slide therein and a sliding sleeve thereon, radially shiftable chasers carried by the body and connected with the sleeve for radially shifts 75 able movement thereof, and a plurality of pivotal connecting members between the slide and sleeve, each of said members having a plurality of .pivotal connections and a pivotal connection with each other, whereby a relative differencel in movement is effected between the slide and sleeve to effect a tapered threading of the work.

2. A die comprising a bodyj an axially shiftablefslide therein and a sliding sleeve thereon, radially shiftable chasers carried by the body i and connected with the sleeve for radially shiftable movement thereof, and a plurality of pivotal connecting membersbetween the slide and sleeve, each of said members having a plurality of pivotal connections and a pivotal connection with each other, whereby a relative difference inv vable slide thereiny and a sliding sleeve thereon,

radially shiftable chasers carried by the body and connected with the sleeve for radially shiftable movement thereof, and a plurality of pivotal connecting members between the slide and sleeve, each of said members having a plurality of pivotal connections and a pivotal connection with each other, whereby a relative difference in movement is effected between the slide and sleeve to effect a tapered threading of the work, each of said pivotal connecting members also having a' pivotal connection with the body.

-4. A die comprising a body, an axially shiftable slide therein and a sliding. sleeve thereon, radially shiftable chasers carried by the body and connected with the sleeve for radially shiftable movement thereof, and a plurality of pivctal connecting members between the slide and sleeve, each of said members having a plurality of pivotal connections and a pivotal connection with each other, whereby a relative difference in movement is effected between the slide and sleeve to effect a tapered threading of the work, each of said pivotal connecting members also having a pivotal connection with the body, one

of said last pivotal connections stationary relative to the body during the thread cutting operation and movable at the end of the thread cutting to shift the cutters to permit removal of the Work.

5. A die comprising a body, an axially shiftable slide therein and a sliding sleeve thereon, radially shiftablechasers carried by the body and connected withthe sleeve for radially shiftable movement thereof, and a plurality of pivotal connecting members between the slide and sleeve, each of said members having a plurality of pivotal connections and a pivotal connection with each other, whereby a relative difference in movement is effected between the slide and sleeve to effect a tapered threading of the work, each of said pivotal connecting members also having a pivotal connection with the body, one of said last pivotal connections lstationary relative to the body during the thread cutting operation and movable at the end of the thread cutting to shift the cutters to permit removal of the work, said last 'pivotal connection also axially adjustable to effect radial adjustment of the cha-sers. i

6. A die comprising a body, an axially shiftable slide therein and a sliding sleevethereon, radially shiftable chasers carried by the body and connected with the sleeve for radially shiftable movement thereof, and a plurality of pivotal connecting members between the slide and sleeve, each of said members having a plurality of pivotal connections and a pivotal connection with each other, whereby a relative difference in movement is effected between the slide and sleeve to effect a tapered threading of the work, each of said pivotal connecting members also having a pivotal connection' with the body, one of said last pivotal connections radially adjustable to effect adjustment of the taper `of the thread to be cut. I

'1. A die comprising a body, an axially shiftable slide therein and a sliding sleeve thereon, radially shiftable chasers -carriefi by the body and connected with the sleeve for radially shiftable movement thereof, a plurality of pivotal connecting members between the slide and sleeve, each of said members having a plurality of pivotal connections and a pivotal connection with each other, whereby a relative difference in movement is effected between the slide and sleeve to effect a tapered threading of the work, and tripping means for tripping the chasers upon completion of the threading operation.

8. A die comprising a body, an axially shiftable slide therein and a sliding sleeve thereon, radially shiftable chasers carried by the body and connected with the sleeve for radially shiftable movement thereof, a plurality of pivotal connecting members between the slide and sleeve, each of said members having a plurality of pivotal connections and a pivotal connection with each other, whereby a relative diiference in movement is effected between the slide and sleeve to .effect a tapered threading of the work, and tripping means both automatically and manually operative for tripping the chasers upon completion of the threading operation.

9. A die comprising a body, an axially shiftable slide therein and a sliding sleeve thereon, radially shiftable chasers carried by the body and connected with the sleeve for radially shiftable movement thereof, a plurality of pivotal connecting members between the slide and sleeve, each of said members having a plurality of pivotal connections and a pivotal connection with each other, whereby a relative difference in movement is effected between the slide and sleeve to effect a tapered threading of the work, tripping means for tripping the chasers upon completion of the threading operation, and means for adjusting the chasers radially.

10. A die comprising a body, an axially shiftable slidetherein and a sliding sleeve thereon, radially shiftable chasers carried by the body and connected with the sleeve for radially shiftable movement thereof, a plurality of pivotal connecting members between the slide and sleeve, each of said members having a plurality of pivotal connections and a pivotal connection `with each other, whereby a relative difference in movement is effected between the slide and sleeve to effect a tapered threading of the work, tripping means for tripping the chasers upon completion of the threading operation, and a plurality of independently operative means for adjusting the chasers radially.

ll. A die comprising a body, an axially shiftable slide therein and a sliding sleeve thereon, radially shiftable chasers carried by the body and connected with the sleeve for radially shiftable movement thereof, a compound pivotal con; necting means between the slide and sleeve whereby a relative difference in movement is effected between the slide and sleeve to effect a tapered threading of the work, tripping means for tripping the chasers upon .completion of the threading operation, and Aa plurality of inde-- pendently operative means for adjusting the chasers radially, one of said ,last means compris- 5 ing radially shiftable members carried bythe body, each having a series of cam slots therein and cam rods carried by the sleeve and co-acting with said cam slots.

12. A die comprising a body, an axially shift- 10 able slide therein and a sliding sleeve thereon, radially shiftable chasers carried by the body and connected with lthe sleeve for radially shiftable fmovement thereof, a plurality of pivotal connecting members between the slide and 15 sleeve,'each of said members having a plurality of pivotal connections and a pivotal connection with each other, whereby a relative difference in movement is effected between the lslide and sleeve to effect a tapered threading of the work, trip- 20 ping means for tripping the chasers upon completion of the threading operation, and a` plurality oi. independently operative means for adjusting the chasers radially, one of said last means comprising means for changing the location of 25 one of the pivotal points of one of said pivotal connecting members.

13. A die comprisinga body, an axially shiftable slide therein and a sliding sleeve thereon, radially shiftable chasers carried by the body 30 and connected with the sleeve for radially shiftable movement thereof, a plurality of pivotal connecting members between the slide and sleeve, each of said members having a plurality of pivotal connections and a pivotal connection 35 with each other, whereby a relative difference in movement is effected between the slide and sleeve to effect a tapered threading of the work, tripping means for tripping the chasers upon completion of the threading operation, and 'ad- 4,0A

justable means for controlling the taper ofthe work.

14. A die comprising a body, an axially shiftable slide thereinand a sliding sleeve thereon, radially shiftable chasers carried by the body 45 and connected with the sleeve for radially shiftable movement thereof, a plurality of pivotal connecting members between the slide and sleeve, each of said members having a plurality of pivotal connections and a pivotal connection 50 with each other, whereby a relative difference in movement is effected between the slide and sleeve to effect tapered threading of the work, tripping means for tripping the chasers upon completion of the threading operation, and a 55 radially shiftable chasers carried by the body 60 andconnected with the sleeve for radially shiftable movement thereof, a plurality of pivotal connecting members between the slide and sleeve, each of said members having a plurality of pivotal connections and a pivotal connection with each other, whereby a relative dierence in movement is effected between the slide and sleeve to effect tapered threading of the work, tripping .means for tripping the chasers upon 70 completion of the threading operation-and a plurality of independently adjustable means for controlling the taper of the work, one of said last means comprising a radially movable holding member carried by the body and a pivotal con- 75 nection between said holding member and one of said pivotal connecting members.

16. A die comprising a body, an axially shiftable slide therein and a sliding sleeve thereon, radially shiftable chasers carried by the body and connected with the sleeve for radially shiftable movement thereof, a plurality of pivotal connecting members between the slide and sleeve, each of said members having aI plurality of pivotal connections and a pivotal connection with each other, whereby a relative diierence in movement is effected between the slide and sleeve to effect tapered threading of thework, tripping means for tripping the chasers upon completion of the threading operation, and a plurality of independently adjustable means for controlling the taper of the Work, one of said last means comprising a holding member carried by the body, a plurality of positioning means carried thereby, and a pivotal connection between said holding member and o ne of said pivotal connecting members and carried by one of said positioning means.

17. A die comprising a body, an axially shiftable slide therein and a sliding sleeve thereon, radially shiftable chasers carried by the body and connected with the sleeve for radially shiftable movement thereof, a plurality of pivotal connecting members between the slide and sleeve, each of said members having a plurality of pivotal connections and a pivotal connection with each other, whereby a relative difference in movement is effected between the slide and sleeve to eiect a tapered threading of the work, tripping means for tripping the chasers upon completion of the threading operation, and a plurality of independently adjustable means for controlling the taper of the work, one of said last means comprising a plurality of pivotal holding means, each adapted for connectingsaid slide and one of said pivotal connecting members.

18. A die comprising a body, an axially shiftable slide therein and a sliding sleeve thereon, radially shiftable chasers carried by the body and connected with the sleeve for radially shiftable movement thereof, a plurality of pivotal connecting members between the slide and sleeve, each of said members having a plurality of pivotal connections and a pivotal connection with each other, whereby a relative difference in movement is eiected between the slide and sleeve to effect a tapered threading of the work, tripping means for tripping the chasers upon completion of the threading operation, and adjustable means for controlling the length of thread of the work.

19. A die comprising a body, an axially shiftable slide therein and a slidingrrsleeve thereon, radially shiftable chasers carried by the body and connected with the sleeve for radially shiftable movement thereof, a plurality of pivotal connecting members between the slide and sleeve, each of said members having a plurality of pivotal connections and a pivotal connection with each other, whereby a relative diierence in movement is effected between the slide and sleeve to effect a tapered threading of the work, tripping means for tripping the chasers upon completion of the threading operation, and adjustable means for controlling the length of threadof the work and comprising an axially movable work engaging member.v

20. A die comprising a body, an axially shiftable slide therein and a 'sliding sleeve thereon, radialv shiftable chasers carried by the body alcance and connected with the sleeve, a transversely extending member pivotally connected with the slide and with the body, a circular member pivotally connected with the sleeve and with the body, and means pivotally connecting said members whereby pivotal movement of said first member eects pivotal movement of said second member thereby to effect a relative difference in movement between the slide and sleeve whereby a tapered threading of the work is obtained.

21. A die comprising a body, radially shiftable chasers carried thereby, a pair of members shiftable axially relative to said body and to each other, one of said members adapted to engage the work, the other of said members adapted to co-act with the chasers to elect a tapered threading of the work, and a plurality of pivotal connecting members for said axially shiftable members, each of said connecting members having a plurality of pivotal connections and a pivotal connection with each other, whereby the 'movement of one of said axially shiftable members relative to the body will effect movement of the other of said axially shiftable members relative to the body and said first axially shiftable member.

22. A die comprising a body, an axially shiftable slide therein and a sliding sleeve thereon, radially shiftable chasers carried by the body and connected with the sleeve, means pivotally connected with the body and slide, and means pivotally connected with the body and sleeve and having a pivotal connection with said rst means spaced from all other of said pivotal connections whereby movement of the slide is transmitted to the sleevein the ratio ofthe difference between the spacing of the pivotal points of connection of the rst means with the body and slide, and its connection with the body and the second means multiplied by the ratio of the dierence between the pivotal points of connection of the second means with the body and sleeve, and its connection with the body and first means thereby to effect a tapered threading of the work.

23. A die comprising a body, an axially shiftable slide therein and a sliding sleeve thereon, radially shiftable chasers carried by the body and connected with the sleeve, a transversely extending member pivotally connected with the slide and with the body, a circular'member pivotally connected with the sleeve and with the body, and means pivotally connecting said members whereby pivotal movement of said rst member effects pivotal movement of said second member thereby to effect a relative difference in movement between the slide and sleeve whereby a tapered threading of the work is obtained, the pivotal'points of said pivotal connecting means movable in lines parallel to the axis of the die.

24. A die comprising a body, an axially shiftable slide therein and a sliding sleeve thereon, radially shiftable chasers carried by the body and connected with the sleeve, a transversely extending member pivotally connected with the slide and with the body, a circular member pivotally connected with the sleeve and with the body, and means pivotally connecting said members whereby pivotal movement of said rst member effects pivotal movement of .said second member thereby to effect a relative difference in movement between the slide and sleeve whereby a tapered threading of the work is obtained, the pivotal points of said pivotal connecting means movable in lines parallel to the axis of the die,

one of said pivotal points stationary relative to the body during the thread cutting operation and movable relative thereto upon completion of the thread cutting operation to effect disengagement of the cutters from the work.

25. A die comprising a body, an axially shiftable slide therein and a sliding sleeve thereon, radially shiftable chasers carried by the body and connected with the sleeve, a transversely extending member pivotally connected with `the slide and with the body, a circular member pivotally connected wtih the sleeve and with the body, and means pivotally connecting said .members whereby pivotal movement of said flrst member effects pivotal movement of said second member thereby to eiect a relative diierence in movement between the slide and sleeve whereby a tapered threading of the work is obtained, the pivotal points of said pivotal connecting means movable in lines parallel to the axis of the die, one of said pivotal points stationary relative to the body during the thread cuttingoperation and movable relative thereto upon completion of the thread cutting operation to effect disengagement of the cutters from the work, and means for eiecting said last movement.

26. A die comprising a body, an axially shiftable slide therein and a sliding sleeve thereon, radially shiftable chasers carried by the body and connected with the sleeve for'radially shiftable movement thereof, and a compound pivotal connecting means between the slide and sleeve whereby a relative difference in movement is effected between the slide and sleeve tov obtain a tapered threading of the work, said compound pivotal connecting means comprising a lever pivotally connected to the body and slide and a yoke pivotally connected to the body and sleeve and having pivotal connection with the lever.

2'7. A die comprising a body',` an axially shift-I able slide therein and a sliding sleeve thereon, radially shiftable chasers carried by the body and connected with the sleeve for radially shiftable movement thereof, a compound pivotal connecting means between the slide and sleevewhereby a relative dierence in movement is effected between the slide and sleeve to obtain a tapered threading of the work, said compound pivotal connecting means comprising a lever pivotally connected to the body and slide and a yoke pivotally connected to the body and sleeve and having pivotal connection with the lever, means for adjusting the chasers radially comprising means for moving a pivotal connection of said yoke,

means for controlling the taper of the work comprising means for moving a pivotal connection of said lever, and means for controlling the length of thread of the work, said last means comprising a movable member secured to said axially shiftable slide.

28. A die comprising a body, an axially shiftable slide therein and a sliding sleeve thereon, radially shiftable chasers carried by the body and connected with the sleeve for radially shiftable movement thereof, 'and a compound pivotal connecting means '-between the slide and sleeve and including a pivoted yoke encircling said body whereby a relative difference in movement is obtained between the slide and sleeve to eiect a tapered threading of the work.

29. A die comprising a body, an axially shiftable slide therein and a sliding sleeve thereon, radially shiftable chasers carried by the body and connected with the sleeve for radially shiftable movement thereof, and a compound pivotal connecting means between the slide and sleeve whereby a relative diierence in movement is effected between the slide and sleeve to obtain a tapered threading of the work, said compound pivotal connecting means comprising a pivoted lever and a pivoted yoke.

30. A die comprising a body, an axially shiftable slide therein and a sliding sleeve thereon, radially shiftable chasers carried by the body and connected with the sleeve for radially shiftable movement thereof, and a compound pivotal connecting means between the slide and sleeve whereby a relative difference in movement is eiected between the slide and sleeve to obtain a tapered threading of the work, said compound pivotal connecting means comprising a pivoted lever and a pivoted yoke pivotally connected to each other. 3l. A die comprising a body, an axially shiftable slide therein and a sliding sleeve thereon, radially shiftable chasers carried by the body and connected with the sleeve for radially shiftable movement thereof, and a compound pivotal connecting means between the slide and sleeve whereby a relative difference in movement is eifected between the slide and sleeve vto obtain a tapered threading of the work, said compound pivotal connecting means comprising a lever and a yoke, one pivotally connected to the body and slide and the other pivotally connected to the body and sleeve and having a pivotal connection with each other.

WILLIAM J. HOGG. 

